1. Technical Field
The present disclosure relates to a power converter apparatus. More particularly, the present disclosure relates to a power converter apparatus with the function of power factor correction.
2. Description of Related Art
Due to the energy crisis in recent years, many countries focus on developing new energy and set up high environmental standard to regulate the specifications of the electronic products, especially to the power factor and total harmonic distortion of the electronic products. For example, some new electricity regulations (e.g., the specification IEC 61000-3-12) have requirements in the total harmonic distortion, and these regulations will affect the designers in product design considerations.
In general, electrical equipments are usually not purely resistive. Non-resistivity of the electrical equipments (whether the electrical equipments are inductive or capacitive) will lead to a poor power factor, which will result in an increased input current and a heavy load on the power supply system. In addition, the serious distortions occurred on the input current may includes a high degree of the harmonic waveform components, which may cause a serious pollution to the power grid network.
Therefore, the quality of the power supply system will be highly elevated if the power factor of the electrical equipment can be improved and the harmonic distortion can be reduced. The traditional power factor improvement circuits involve two major categories of passive-type power factor improvement circuits and active-type power factor improvement circuits. The passive power factor improvement circuits utilize passive components (such as inductors, capacitors) to improve the power factor. The passive-type power factor improvement circuits have advantages of their simply construction. However, the passive-type power factor improvement circuits have disadvantages of huge sizes and limited abilities in power factor correction.
On the other hand, the active-type power factor improvement circuits utilize additional circuitry to achieve the purpose of power factor correction. The active-type power factor improvement circuits have smaller sizes, lighter weights, and higher power factors compared to the passive-type power factor improvement circuits. However, the traditional active-type power factor improvement circuits involve complex external circuits, and the traditional active-type power factor improvement circuits must be re-calibrated or re-modeled in order to match different ratios of harmonic waveform components.